KR19990072305A - Commutator and method of manufacturing the same - Google Patents

Abstract

The commutator 50 includes a contact body 510, a base member 520 made of an insulating material, and a terminal body 530. The contact body 510 has a planar brush contact surface 510a and a connection surface on the opposite side thereof. Contact 510 also has a plurality of commutator segments 511. The terminal body 530 has a plurality of conductive terminal members 531. The base member 520 supports the commutator fragments 511. The commutator 50 is also disposed between a set of convex members 510b and concave members 531b and 530b, and between these convex members 510b and concave members 531b and 530b to form the plurality of commutator segments ( 511 and the terminal member 531 has an electrical connection structure including a plurality of connecting members 512 for interconnecting.

Description

Commutator and its manufacturing method {COMMUTATOR AND METHOD OF MANUFACTURING THE SAME}

The present invention relates to a commutator composed of carbon fragments, more particularly to a commutator for a fuel injection pump motor and a method of manufacturing the same.

Rectifiers consisting of multiple carbon fragments are disclosed in US Pat. No. 5,175,463. Commutators in the same name are isolated from each other by several grooves. The commutator has a plurality of terminal members disposed in parallel with the back surfaces of the carbon fragments and connected to these carbon fragments via filler metal or solder brazing. The back of the carbon fragments connected to the terminal members are coated to ensure a secure connection.

However, when connecting the terminal members by fusing or the like with leads extending from the rotor windings, heat transfer to the brazing filler material occurs through a relatively short heat transfer path of the terminal terminals. Accordingly, brazing filler may dissolve to short-circuit the carbon fragments.

It is a main object of the present invention to provide an improved commutator segment that is free from short concerns in assembling a finished motor.

It is another object of the present invention to provide a commutator having a relatively long heat transfer path from the lead connection of the terminal member to the solder with the commutator segments.

Another object of the present invention is to provide an improved electric motor which can be used in a corrosive environment such as fuel.

Another object of the present invention is to provide a method for producing such commutator fragments at low production costs.

1 is a longitudinal sectional view of a commutator according to a first embodiment of the present invention;

2 is a cross-sectional view taken along line 1-1 of FIG. 1;

3 is a side sectional view showing a fuel pump equipped with a commutator according to a first embodiment;

4 is a side sectional view showing a modification of the commutator according to the first embodiment;

5 is a longitudinal sectional view showing a modification of the commutator according to the first embodiment;

6 is a cross-sectional view taken along line 6-6 of FIG. 5;

7 is a longitudinal sectional view of a commutator according to a second embodiment of the present invention;

8 is a cross-sectional view taken along line 8-8 of FIG.

9 is a side sectional view showing a commutator according to a second embodiment;

Fig. 10 is a partial sectional side view of a main part of a modification of the commutator according to the second embodiment;

11 is a side cross-sectional view of a main part of a commutator according to a third embodiment of the present invention;

12 is a graph showing the temperature change of each part of the terminal member with respect to time;

13 is a graph showing the correlation between the distance from the rotation axis and the temperature change of each part of the terminal member;

14 is a partial cross-sectional side view of a main part of a modification of the commutator according to the third embodiment;

15 is a side sectional view showing a modification of the commutator according to the third embodiment;

16A is a side sectional view showing a modification of the commutator according to the third embodiment;

16B is a cross-sectional view taken along line 16B-16B of FIG. 16A;

17A is a side sectional view showing a modification of the commutator according to the third embodiment;

17B is a cross-sectional view taken along line 17B-17B of FIG. 17A;

18 is a schematic partial sectional view of a modification of the commutator of the third embodiment;

19 is a longitudinal sectional view of a commutator according to a fourth embodiment of the present invention;

20 is a longitudinal sectional view of a modification of the commutator according to the fourth embodiment;

21 is a longitudinal sectional view of a commutator according to a fifth embodiment of the present invention;

Fig. 22 is a side sectional view showing a modification of the commutator according to the fifth embodiment;

23 is an enlarged partial sectional view of a modification of the commutator according to the fifth embodiment;

24 is an enlarged partial sectional view of a modification of the commutator according to the fifth embodiment.

Explanation of symbols on main parts of drawing

50: commutator 510: contact

511: commutator intercept 512: connecting member

520: base member 530: terminal body

The main feature of the present invention is a commutator comprising a contact having a planar brush-contact surface and a connection surface, a base member of insulating material, and a terminal body. The contact has a plurality of commutator segments, and the terminal body has a plurality of conductive terminal members. The base member supports the commutator segments, while isolating these segments from each other. The commutator also constitutes an electrical connection structure having a set of convex and concave members and a plurality of connecting members disposed therebetween.

Preferably, the convex member has a plurality of protrusions extending axially from the contact body, and the concave member has the terminal body portion associated with these protrusions. The contact body and the terminal body are separated from each other except for the above connection structure.

An isolation spacer may be disposed between the contact and the terminal body. By doing so, the molding process of the base member can be simplified. The electrical connection structure may include a rise member disposed between the contact member and the terminal member to prevent leakage of the connection member upon dissolution of the connection member.

Another main feature of the present invention is a method of manufacturing a commutator comprising a contact having a flat brush contact surface and a connection surface, a base member made of an insulating material, and a terminal member.

The method comprises the steps of forming a rigid carbon disk having a plurality of axially extending arcuate protrusions, applying a conductive material to the outer circumferential surface of the arcuate protrusions, and a brass ring member having a plurality of through holes. forming a member) and assembling the carbon disk and the brass ring such that the arcuate protrusions are placed into the through hole, respectively, to form a suitable molding space between the rigid carbon disk and the brass ring; Inserting a solid solder into a connection space defining a hole and an inner surface of the arcuate protrusion, heating the solder to dissolve in the connection space, filling a resinous insulating material in the molding space; Obtaining a plurality of commutator segments and terminal members by cutting the rigid carbon disk and ring members. It is open configuration.

Functions and other objects and features of each related part in the present invention will be apparent from the following detailed description, the appended claims and the drawings.

(First embodiment)

A commutator according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. The commutator indicated by the reference numeral '50' is used for the fuel pump 10, as shown in FIG. The fuel pump 10 is composed of a pump unit 20 and the DC motor unit 30. The motor unit 30 has an annular permanent magnet on the inner circumferential surface of the cylindrical housing 11 and a rotor rotor 32 inside the permanent magnet. The pump portion 20 has an aluminum casing 21, an aluminum casing cover 22, and an impeller 23. The casing cover 22 is clamped to the tip of the casing 21. The rotor rotor 32 has a shaft 35, which is supported by the radial bearing 25 and the thrust bearing 26 at one end thereof and the radial bearing 27 at the other end. The casing cover 22 has a fuel inlet 40, through which the fuel is injected into a C-type pump passage 41 formed around the impeller 23. The fuel in the pump passage 41 is supplied to the fuel chamber 31 by the impeller 23 of the motor unit 30. The rotor rotor 32 has a rotor core 32a wound around the rotor windings. Disc-shaped commutator 50 is fixed to the upper portion of the rotor rotor 32 serves to supply power to the rotor windings. When electric power is applied from the battery to the rotor winding via the terminal 46, the rotor rotor 32 rotates to rotate the impeller 23, thereby providing a fuel passage (from the fuel inlet 40). Fuel is injected into 41 and supplied to the fuel chamber 31. The fuel then passes around the rotor rotor 32 and exits to the fuel outlet 43. The fuel outlet 43 is equipped with a check valve 44 for preventing backflow of fuel.

As shown in FIG. 2, the commutator 50 is composed of a contact member 510, a base member 520 made of thermoplastic resin, and a terminal body 530. The contact member 510 has a planar brush contact surface 510a at one end thereof and eight arcuate protrusions or projections 510b extending in the axial direction at the other end thereof.

As shown in FIG. 1, the contact body 510 includes eight circular arc-shaped carbon fragments 511 that are supported by the resin base member 520 and are arranged in a circular manner with an isolation groove therebetween. It is composed.

The terminal body 530 is composed of eight brass terminal members 531 that are supported by the base member 520 and are circularly arranged in a state separated from each other by the radial isolation grooves 510c. Each terminal member 531 has a rectangular through hole or recess 531b fmf to be brought into contact with the hook 531a and the arcuate protrusion 510b. Leads extending from the rotor windings are connected to the respective hooks 531a through fusing and the like. The rectangular through holes 531b also provide a connection space inside the arcuate protrusion 510b. Solder connection members or blazing charging members 512 are filled in the connection space to electrically connect the respective sections 511 with the corresponding terminal member 531.

The commutator 50 is manufactured as follows.

(1) A rigid carbon disk having eight arcuate protrusions extending in the axial direction is formed, and a conductive material is applied to the outer circumferential surface of the arcuate protrusions.

(2) A brass ring member having eight rectangular through holes 531b is formed.

(3) Assemble the solid carbon and brass rings to support these protrusions with a tool with the arc-shaped protrusions inserted into the rectangular through holes, respectively, so that a suitable molding space is formed between the rigid carbon disk and the brass ring. do.

(4) The connecting member 512 is formed by inserting solid solder into the connecting space formed between the through hole and the arcuate protrusion, heating and dissolving therein.

(5) After removing the support tool, a resin material is filled into the molding space to form a base member 520 to form a square commutator.

(6) By forming eight elongated grooves 510c, the solid disk and the ring are divided into eight segments 511 and eight terminal members 531. That is, the commutator 50 is to be made.

The main electrode of the fusing device is placed on the outer circumference of the hook while the other electrode is placed on the portion of the terminal member 531 remote from the main electrode, thereby connecting the leads of the rotor winding to the hooks 531a. do. Before the lead is soldered with the hook 531a, the insulating film on the lead is melted due to Joule heat.

Although the joule heat is conducted from the hook 531a to the connecting member 512, the connecting member 512 may remain in a solid state as the heat is dissipated due to the relatively long conductive path. Although a portion of the connecting member 512 may be dissolved, the molten solder may not reach any of the grooves 510c due to the base member 520. That is, the short between the segments 511 is prevented.

As a modification of the commutator 50 according to the first embodiment of the present invention, as shown in FIG. 4, the isolation spacer 521 having eight rectangular through holes corresponding to the through holes 531b prior to forming the base member. You can also insert). In this structure, the pressure in filling the isolation material into the molding space can be reduced by making the tool for forming a suitable molding space unnecessary.

As another modification of the commutator 50 according to the first embodiment, as shown in Figs. 5 and 6, the terminal body 530 has a center hole 530a instead of the rectangular through holes 5301b. The diameter of the central hole 530a is larger than the outer diameter of the eight arc-shaped protrusions to sufficiently accommodate the connecting member 512. Since the connecting member 512 is located away from the hook 531a, the contact 510 does not need to be separated from the terminal body 530.

Second Embodiment

The commutator 50 according to the second embodiment of the present invention will be described with reference to FIGS. 7 to 9.

The commutator 50 includes a contact body 510, a base member 520, and a terminal body 530. The contact body 510 has a planar brush contact surface 510a at one end thereof and eight cylindrical protrusions 510b extending in the axial direction at the other end thereof. The contact body 510 includes eight carbon fragments 511 supported by the resin base member 520. The carbon fragments 511 are separated from each other due to the isolation grooves 510c. The terminal body 530 includes eight brass terminal members 531 supported by the base member 520. The terminal member 531 is also spaced from each other by the isolation groove (510c). That is, each section 511 is aligned with one terminal member 531 between two grooves 531c. Each terminal member 531 has a hook 531a and a contact surface 531b in contact with the contact member 512. A lead extending from the rotor winding is clamped with one of the hooks 531a and connected thereto by fusing or the like. As shown in FIG. 9, the terminal body 530 has the normal octagonal center hole 530a which circumscribes the outer peripheral part 510d of a cylindrical protrusion part. Eight semi-cylindrical recesses 530b are formed at each corner or apex of the octagonal hole 530a, so that connection spaces are formed between the outer circumference 510d and the inner circumference of the central hole 530a. Solder connection members 512 are filled in the connection space to electrically connect the respective sections with a corresponding one terminal member.

The commutator 50 is manufactured as follows.

(1) Form a rigid carbon disk having eight rigid cylindrical projections extending in the axial direction, corresponding to the cylindrical projection 510b.

(2) A brass ring having a square octagonal center hole corresponding to the center hole 530a is formed. The center hole may be in contact with the outer circumference of the cylindrical protrusion, such that the cylindrical protrusion may be supported in position. That is, the connection space is formed evenly around the cylindrical protrusion.

(3) As the solid solders are inserted into the connecting space, heated and melted therein, the molten solder flows from the connecting space into the gap between the cylindrical protrusion and the ring member, thereby removing these cylindrical protrusions and the ring member. The connecting member 512 is formed to connect.

(4) The carbon disc and the ring member are molded together with the resin isolation material to form a square commutator. The solid disk and ring are then divided into eight segments 511 and eight terminal members 531 by forming eight elongated grooves 510c. That is, the commutator 50 is to be made.

When connecting the leads of the rotor winding to the hooks 531a by fusing, fusing heat is conducted from these hooks 531a to the connecting member 512. However, as the heat is dissipated due to the relatively long conducting path, the connecting member 512 can maintain its robustness, thereby ensuring a reliable electrical connection.

A modification of the second embodiment is shown in FIG. 10 with the vertical inversion state. The cylindrical protrusion 510b has an inclined or chamfered surface and an annular protrusion 510e. The inclined surface provides an open gate for molten solder, and the protrusion 510e serves to prevent leakage of the molten solder.

(Third Embodiment)

The commutator 50 according to the third embodiment of the present invention will be described with reference to FIG.

The contact 510 receives the connecting member 512 by having an annular groove 510f on the surface facing the terminal body 530. A conductive material is applied to the surface of the annular groove 510f, and a flux is applied to the terminal body-side connection surface in contact with the groove to increase the viscosity of the solder. It is also possible to apply polytetrafluoroethylene or equivalent to other surfaces that are not connected.

FIG. 12 is a test result showing the correlation between the fusing start point, the end point, and the temperature and time of three points P1, P2, and P3 on the terminal member 531 when the specimen is cooled at room temperature. Point P1 is located in the portion of the terminal member 531 adjacent to the hook 531a, point P2 is located in the middle portion thereof, and point P3 is a portion adjacent to the connecting member 512. Although the temperature of the point P3 rises after completion of fusing, even if a fusing current fluctuates to the maximum value, the temperature is 200 degrees C or less and tin melting point 230 degrees C or less.

As shown in FIG. 14, the annular groove 530c formed on the terminal body 530 may be replaced with the annular groove 510f formed on the contact body 510.

As shown in Fig. 15, the annular projection 510e is formed on the surface of the contact 510 facing the terminal body 530, whereby the connecting members 512 are formed inside the annular projection 510e. It can hold | maintain in the space between 510 and the terminal body 530. When the connecting member 512 is molded from the molten solder material, the annular protrusion 510e is effective in collecting molten solder into the space.

Instead of the annular projection 531c, as shown in Figs. 16A and 16B, a C-shaped projection 531c may be formed on each terminal member 531. That is, the protrusion 531c exerts its effect in preventing leakage of molten solder during the forming process of the connecting member 512. The projections corresponding to the C-shaped projections 531c may be formed on the respective segments 511 of the contact body 530.

As shown in FIGS. 17A and 17B, a pair of radial projections 531d may be formed on both sides of each terminal member 531. Each of these protrusion pairs has an effect of preventing the outflow of molten solder. That is, even if a part of the connection member 512 is dissolved, the shorting can be prevented. Instead of the terminal member 531, each of the radial protrusion pairs may be formed on the section 511.

As shown in FIG. 18, each of these protrusion pairs 520e can be formed on the base member 520, and can be inserted into a pair of recessed portions formed along both sides of each terminal member 531. As shown in FIG. Each pair of protrusions 520e also has an effect of preventing the leakage of molten solder.

(Example 4)

A commutator according to a fourth embodiment of the present invention will be described with reference to FIG. 19.

Contact 510 has a star-shaped protrusion 510b with eight protruding edges. The terminal body 530 has an octagonal center hole 530a circumscribed to the eight protruding edges. The connecting members 512 are positioned in the space between the inner circumference of the central hole 530a and the outer circumference of the star protrusion.

As shown in FIG. 20, by forming the concave portions 530b, the volume of the connecting member 512 on the inner circumferential portion of the central hole 530a may be increased between the protruding edges.

(Example 5)

A commutator according to a fifth embodiment of the present invention will be described with reference to FIG. 21.

This commutator is comprised by the inverted center hole which has eight protrusion parts which contact the outer peripheral part of an invisible cylindrical protrusion between eight recessed parts 530b.

Therefore, the volume of the connecting members 512 can be increased, thereby ensuring a stable connection even if the size of the components changes.

The cylindrical protrusion 510 may also have an inclined or chamfered surface as in FIGS. 22 and 23. When the commutator is assembled and heated, the inclined surface of the carbon cylindrical protrusion 510 is wider than the surface of the terminal member 531 in contact with the connecting member 512, so that the solder portion in contact with the cylindrical protrusion is in contact with the ring member. It dissolves before the solder part. The molten solder joins the terminal members 531 by flowing into the corresponding ring member. That is, the cylindrical carbon protrusion 510 and the brass ring member can be reliably soldered.

Instead of the inclined surface of the cylindrical protrusion 510, as shown in FIG. 24, the terminal member 531 may have an inclined surface. That is, the volume of the connecting members 530b can be increased, thereby ensuring a stable connection even if the size of the components changes.

The present invention has been described in detail above with reference to preferred embodiments. However, various modifications or variations are possible without departing from the basic spirit of the invention as set forth in the appended claims. In other words, what is described in this specification should be construed in the meaning of description only rather than any limitation.

As described above, according to the commutator of the present invention and the manufacturing method thereof, it is possible to obtain not only the quality improvement by fundamentally excluding the possibility of short generation during the motor assembly process, but also the effect of reducing the manufacturing cost.

Claims (13)

A contact body 510 for accommodating a plurality of commutator segments 511 and having a planar brush contact surface 510a and a connection surface opposite the brush contact surface 510a, and supporting the commutator segments 511 and made of an insulating material. In the commutator 50 comprising a base member 520 and a terminal body 530 having a plurality of conductive terminal members 531, In order to connect a set of convex members 510b and concave members 531b and 530a, and the plurality of commutator segments 511 and the terminal members 531, respectively, the convex members 510b and concave members 531b. Commutator 50, characterized in that it comprises an electrical connection structure having a plurality of connecting members 512 disposed between the 530b. The convex member 510b includes a plurality of protrusions extending axially from the contact body 510, and the concave members 531b and 530b are coupled to the protrusions. 530) commutator 50, characterized in that it comprises a portion. The commutator (50) of claim 2, wherein the contact member (510) and the terminal member (530) are separated from each other by the base member (520) except for the connection structure. 4. The commutator (50) according to claim 3, further comprising an isolation spacer (521) disposed between said contact (510) and said terminal body (530). The electrical connection structure of claim 1, wherein the electrical connection structure includes a protrusion member (510e, 531c, 531d) disposed between the contact member (510) and the terminal member (530) in order to prevent leakage of the connecting member. Commutator 50 characterized in that it comprises. 6. The commutator (50) according to claim 5, wherein the protruding member (520e) includes a plurality of members extending from the base member (20) and surrounding the opposite sides of the respective terminal members (531). 3. The terminal of claim 2, wherein the plurality of protrusions typically have a cylindrical outer circumference, and the terminal body 530 has a regular regular polygonal surface 530a to which the cylindrical outer circumferential vertices are inscribed, wherein each of the connecting members comprises: A commutator (50), characterized in that it is arranged in a connection space specified by a cylindrical outer periphery between one of the vertices, the polygonal surface, one of the segments (511) and the corresponding one terminal member (531). 8. The commutator (50) of claim 7, wherein each of the vertices has a recess (530b) that gradually merges with the polygonal surface. 8. The commutator (50) according to claim 7, wherein the cylindrical outer circumferential portion has a chamfer portion, thereby forming the connecting space in an axially expanded form. A contact body 510 for accommodating a plurality of commutator segments 511 and having a planar brush contact surface 510a and a connection surface opposite the brush contact surface 510a, and supporting the commutator segments 511 and made of an insulating material. In the method for manufacturing a commutator 50 including a base member 520 and a terminal body 530 having a plurality of conductive terminal members 531, Forming a rigid carbon disk having a plurality of axially extending protrusions; Applying a conductive material on the outer circumferential surface of the protrusion; Molding a brass ring member having a plurality of through holes; Assembling the carbon disk and the brass ring such that the arcuate protrusion passes through the through hole so that a suitable molding space is formed between the rigid carbon disk and the brass ring; Inserting solder into a connection space formed between the through holes and the inner surface of the arcuate protrusion; Forming a connecting member by heating the solder to dissolve in the connecting space; Molding the base member 520 by filling a resin isolation material into the molding space; Forming the plurality of commutator segments (511) and terminal member (531) by cutting the rigid carbon disk and the ring member. 11. The method of claim 10, wherein shaping the carbon disk comprises shaping the recess for receiving the solid solder. 11. The method of claim 10, wherein forming the brass ring member comprises forming a recess for receiving the solid solder. A contact body 510 for accommodating a plurality of commutator segments 511 and having a planar brush contact surface 510a and a connection surface opposite the brush contact surface 510a, and supporting the commutator segments 511 and made of an insulating material. In the method for manufacturing a commutator 50 including a base member 520 and a terminal body 530 having a plurality of conductive terminal members 531, Forming a rigid carbon disk having a rigid cylindrical protrusion extending axially; Forming a brass ring member to have a regular polygonal central hole in which the outer circumferential portion of the cylindrical protrusion is inscribed; Inserting a solid solder into a space between the central hole and an outer circumferential portion of the cylindrical protrusion; Heating the solder to dissolve it in the space such that the molten solder flows into the gap between the cylindrical protrusion and the ring member; Molding the base member 520 by molding the rigid disk and the ring member together with a resin material; And dividing said rigid disk and said ring member into said plurality of segments (511) and terminal member (531) by forming elongated grooves.